Suspended Axle For Sprayer

ABSTRACT

A vehicle is provided with an axle suspended from a main frame of the vehicle by right- and left-hand pairs of connecting rods. As viewed from the top, one of each of the right- and left-hand pairs of connecting rods crosses the other of the pair of rods, and, as viewed from the side, the right- and left-hand pairs of rods are disposed parallel to each other. This arrangement of the connecting rods results in the axle moving substantially vertically up and down during operation of vehicle over uneven terrain.

FIELD OF THE INVENTION

The present invention relates to vehicle suspensions, and moreparticularly relates to a suspension for a self-propelled agriculturalsprayer.

BACKGROUND OF THE INVENTION

One known self-propelled sprayer is provided with a suspensionarrangement having each of four drive wheels of the sprayer suspendedindependently, one each at opposite ends of front and rear axles thatare fixed to the main frame of the sprayer. The suspension for each ofthe wheels includes a large complicated, machined casting fixed to oneend of an associated axle and which works together with expensive chromespindles which telescope within upright sleeves defined by the castingso as to permit relative motion between the wheel and the axle.

Another known self-propelled sprayer avoids the costs associated withthe machined casting and chrome spindles by suspending the axles by theprovision of a pair of connecting rods coupled between the vehicle mainframe and each of opposite ends of the axle, and by providing a fifthconnecting rod that serves as a lateral stabilizer bar. This suspensiondesign suffers from the drawback that the axle swings in an arc aboutthe attachment points of the lateral stabilizer bar creating trackingissues as the suspension goes up and down.

Accordingly, the problem to be solved is that of providing a wheelsuspension for a self-propelled sprayer which overcomes the drawbacksassociated with the prior art suspensions.

SUMMARY OF THE INVENTION

According to the present invention, there is provided a vehicle axlesuspension including a plurality of connecting rods.

An object of the invention is to provide a relatively simple vehicleaxle suspension including suspension rods arranged in a manner forresulting in the opposite ends of the axle undergoing near vertical upand down motion as the vehicle travels over uneven ground.

The foregoing object is accomplished by suspending each end of the axlefrom the vehicle frame by a pair of connecting rods arranged such thatas viewed from the side, they are connected in parallel, and as viewedfrom the top one crosses the other.

The foregoing and other objects will become apparent from a reading ofthe ensuing description together with the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a top view of a sprayer vehicle frame with front and rearaxles being suspended in accordance with the principles of the presentinvention.

FIG. 2 is a left side view of the sprayer vehicle frame and axlesuspensions shown in FIG. 1.

FIG. 3 is an enlarged view of a forward region of the vehicle frame andaxle suspension shown in FIG. 2, but with the wheels removed.

FIG. 4 is a left front perspective view of the forward region of thevehicle frame and axle suspension shown in FIG. 3.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Referring now to FIGS. 1 and 2, there is shown a chassis 10 of a highclearance agricultural vehicle, such as a self-propelled agriculturalfield sprayer, including a main frame 11 supported on a front pair ofdriven, steerable ground wheels 12 and a rear pair of driven,non-steerable ground wheels 13.

The main frame 11 comprises transversely spaced, right- and left-hand,fore-and-aft extending parallel beams 14 and 16, respectively. The beams14 and 16 are fixed relative to each other by cross members in the formof front and rear, generally V-shaped: suspension rod mounting brackets18 and 20, respectively. The front bracket 18 is spaced to the rear fromfront ends of the beams 14 and 16 and has opposite vertical ends 22 and24, respectively engaged with, and secured, as by bolts (not shown),against outer faces of the beams. The rear bracket 20 is spacedforwardly from rear ends of the beams 14 and 16 and has oppositevertical ends 26 and 28 respectively engaged with, and secured, as bybolts (not shown) against, the outer faces of the beams 14 and 16.

Extending beneath each of front and rear end regions of, and disposedcrosswise relative to, the parallel beams 14 and 16 are front and rearaxles 30 and 32, respectively. Referring now also to FIGS. 3 and 4, itcan be seen that the front axle 30 includes a main central section 34defined by a tube having a square cross section. Joined in dependingrelationship to opposite ends of the central section 34 are right andleft spindle housings, or drop knees 36 and 38, respectively, which areeach inclined upwardly and inwardly at a relatively small angle tovertical. Fixed to, and respectively projecting forwardly from, upperend regions of the drop knees 36 and 38 are right and left steeringcylinder mounting arms 40.and. 42. Similarly, the rear axle 32 includesa main central section 44 defined by a tube having a square crosssection. Joined in depending relationship to opposite ends of thecentral section 44 are right and left drop knees or spindle housings 46and 48, respectively, which are each inclined upwardly and inwardly at arelatively small angle to vertical.

Right and left hand front spindles (not visible) are respectivelymounted for oscillating in the drop knees 36 and 38. Upper ends of thespindles 50 and 52 project from tops of the drop knees 36 and 38, andare respectively coupled, as by cap screws 50 and 52, to right and leftsteering arms 54 and 56. Formed integrally with the bottom ends of thespindles are wheel support and motor housings 58 and 60, with ahydraulic wheel motor 62 being bolted to a mounting surface 64 of eachof the housings 58 and 60 and being coupled, in a manner not shown, fordriving the front wheels 12. A right steering cylinder 68 is coupledbetween the right mounting arm 40 and the right steering arm 54, while aleft steering cylinder 70 is coupled between the left mounting arm 42and the left steering arm 56.

Mounted for oscillating in the drop knees 46 and 48 of the rear axle 32are right and left rear spindles 72 and 74, respectively. Formedintegrally with a bottom end of the spindles 72 and 74 are right andleft wheel support and motor housings 76 and 78. A hydraulic drive motor80 is bolted to an outwardly facing mounting surface (not shown) of eachof the wheel support and motor housings 76 and 78, and is coupled fordriving an associated one of the non-steerable rear wheels 13.

The front and rear axles 30 and 32 are respectively suspended from themain frame 11 by substantially identical front and rear suspensionarrangements 84 and 86, which are mirror images of each other, with onlythe front suspension arrangement 84 being shown and described in detailfor the sake of brevity.

The front suspension arrangement 84 comprises a middle suspension rodconnection bracket joined to, and projecting rearwardly from, an uppercentral location of the middle section 34 of the front axle 30 andincluding a pair of right and left, upper suspension rod mounts 88 and90, respectively. Located approximately midway between a right end ofthe axle middle section 34 and the right upper mount 88 is a right,lower suspension rod connection bracket including a right, lowersuspension rod mount 92. Similarly, located approximately midway betweena left end of the axle middle section 34 and the left upper mount 90 isa left, lower suspension rod mount 94. As viewed from the top in FIG. 1,the distance between the upper mounts 88 and 90 is substantially equalto the distance between the right upper mount 88 and the right lowermount 92, and, to the distance between the left upper mount 90 and theleft lower mount 94.

Joined to and projecting forwardly from a lower middle location of thefront suspension rod mounting bracket 18 is a pair of right and leftlower suspension rod connection mounts 96 and 98, respectively.Respectively joined to, and projecting forwardly from, upper right andleft end locations of the bracket 18 are an upper pair of suspension rodconnection mounts 100 and 102. As viewed from the top in FIG. 1, thespacing between the lower mounts 96 and 98 is substantially equal to thespacing between the right lower mount 96 and the right upper mount 100,and the spacing between the left lower mount 98 and the left upper mount102.

An upper pair of right and left suspension rods 104 and 106 have forwardends respectively coupled to the upper pair of mounts 88 and 90, andhave rear ends respectively coupled to the upper pair of mounts 100 and102. Similarly, a lower pair of right and left suspension rods 108 and110 have forward ends respectively coupled to the lower right and leftsuspension rod connection mounts 92 and 94, and have rear endsrespectively coupled to the lower right and left suspension mounts 96and 98.

As viewed from the side in FIG. 3, the upper pair of suspension rods 104and 106 are parallel to the lower pair of suspension rods 108 and 110.Thus the axle 30 and attached wheels 12 travel substantially verticallyduring travel over uneven ground. In order to constrain sideways motionof the wheels 12 as they travel up and down, the right set of upper andlower suspension rods 104 and 108, as viewed from the top in FIG. 1, arearranged relative to each other so as to form an X, with the left set ofupper and lower suspension rods 106 and 110 being arranged in a similarfashion.

Up and down motion of the front axle 30 is cushioned by right and leftairbags 112 and 114, having upper ends respectively coupled to right andleft horizontal mounting plates 116 and 118 respectively fixed to andprojecting outwardly from forward end regions of outer faces of theright and left beams 14 and 16; and having lower ends respectivelycoupled to right and left airbag connection by left and right airbagconnection brackets (only left hand bracket 122 is visible) respectivelyprojecting upwardly from right and left end regions of the centralsection 34 of the front axle 30. Further cushioning of up and downmovement of the axle 30 is provided in conjunction with that afforded bythe airbags 112 and 114 by right and left shock absorbers 124 and 126having respective upper ends coupled to right and left upper mounts 128and 130, respectively fixed to and projecting outwardly from the beams14 and 16 at locations just forward of the airbag mounting plates 116and 118, and having respective lower ends coupled to right and leftlower mounts (only the right mount 132 is visible) respectively fixed tolower front locations, of the central axle section 34, which are inapproximate vertical alignment with the upper mounts 128 and 130.

Up and down motion of the rear axle 32 is similarly cushioned by rightand left rear airbags and right and left rear shock absorbers, with thedrawings having only a clear showing of a left airbag 134 and a leftshock absorber 136 (see FIG. 2).

It will be appreciated then that the suspended front and rear axles 30and 32 permit vertical movement of the axles making it unnecessary toprovide expensive chrome spindles as are needed with the fixed axledesign disclosed in the aforementioned U.S. Pat. No. 7,168,717. Further,it will be appreciated that by arranging the side-by-side sets of upperand lower suspension bars so that they each form an X, as viewed fromthe top, a substantially straight line or vertical up and down movementof the axle occurs which eliminates the arc motion generated fromlateral stabilizer bars used in prior art suspensions, thus eliminatingtracking issues that occur when the axle swings in ah arc about theattachment points of the lateral stabilizer bar.

While two pair of upper and lower suspension rods are used for eachaxle, it is noted that for some applications a single pair might providean adequate axle suspension.

Having described the preferred embodiment, it will become apparent thatvarious modifications can be made without departing from the scope ofthe invention as defined in the accompanying claims.

1. In a vehicle including a main frame, an axle extending beneath themain frame and a suspension coupled between the axle and the frame forallowing up and down movement of the axle: relative to the frame, saidsuspension comprising: at least one pair of connecting rods coupledbetween a middle region of said axle and said main frame, with said pairof connecting rods, when viewed from the top, defining an X, and whenviewed from the side, being parallel with each other.
 2. The vehicle, asdefined in claim 1, wherein said suspension includes a second pair ofconnecting rods connected between said frame and axle and being disposedrelative to each other in a fashion identical to how said connectingrods of said at least one pair of connecting rods are disposed relativeto each other.
 3. In a vehicle including a main frame, an axle extendingbeneath the main frame and a suspension coupled between the axle and themain frame for allowing up and down movement of the axle relative tosaid main frame, said suspension comprising: a first upper pair, and afirst lower pair, of connecting rod mounts fixed to said axle, with saidupper pair, as viewed from the top, being centered between opposite endsof said axle and located between said lower pair of connecting rodmounts; a second upper pair, and a second lower pair, of connecting rodmounts fixed to said main frame in longitudinally spaced relationship tosaid axle, with said second lower pair of connecting rod mounts beingcentered between said second upper pair of connecting rod mounts, asviewed from the top; an upper pair of connecting rods having first endsrespectively coupled to one and another of said first upper pair ofconnecting rod mounts, and having second ends respectively coupled toone and another of said second upper pair of connecting rod mounts; anda pair of lower connecting rods having first ends respectively coupledto one and another of said first lower pair of connecting rod mounts,and having second ends respectively coupled to one an another of saidsecond lower pair of connecting rod mounts; and said first and secondupper pairs of connecting rod mounts being so located relative to saidfirst and second lower pairs of connecting rod mounts that, as viewedfrom the side said upper pair of connecting rods extend parallel to saidlower pair of connecting rods, and as viewed from the top, one of saidpair of upper connecting rods cooperates with one of said pair of lowerconnecting rods to form an X, and another of said pair of lowerconnecting rods cooperates with another of said pair of lower connectingrods to form an X.
 4. In a vehicle including a main frame, an axleextending beneath the main frame and a suspension coupled between theaxle and the main frame for allowing up and down movement of the axlerelative to said main frame, said suspension comprising: at least onepair of connecting rods cooperating with each other to form an X, asviewed from the top, and having first ends coupled to said axle andhaving second ends coupled to said frame, with said first and secondends of said connecting rods being so located relative to each otherthat said at least one pair of connecting rods are parallel, as viewedfrom the side.
 5. The vehicle, as defined in claim 4, wherein a secondpair of connecting rods arranged identically to said at least one pairof connecting rods are connected between said axle and said frame, withsaid at least one and second pairs of connecting rods being located soas to respectively define first and second sets of connecting rods that,as viewed from the top, are arranged side-by-side and are centeredbetween opposite ends of said axle.